these 7 derivations will be built:
  /nix/store/5x9y43yrpggf5lq394qxw68blbfi1cnc-futures-task-0.3.34.drv
  /nix/store/9cq4mml371fplbmb05rnhsxddqwz6xcs-futures-sink-0.3.34.drv
  /nix/store/a18lmm5hl9bmv5l338cz3b4vvy79gl0i-futures-util-0.3.34.drv
  /nix/store/rlra6cdzcrsgb6wmr88k3hpvk3c45sdq-futures-core-0.3.34.drv
  /nix/store/sldx66034xn5ca06cmhd8rqyq7dwawan-futures-macro-0.3.34.drv
  /nix/store/8izw9gjdpl1wj251qi9r1ss4w32rfc3s-cargo-vendor-dir.drv
  /nix/store/9sm5b3k206pxq7982cnwslrggh80jwdj-fast-nix-gc-proptest-0.1.0.drv